B&S 10 hp vertical shaft starter question

Chuck Gibson

Forum Newbie
Joined
Mar 21, 2016
Threads
1
Messages
6
I just completed overhauling this motor and had it bored to .030. After assembling it I tried to start it and the starter was dragging. It did manage to give it enough turn to start it but it only ran about 20 seconds before dying. The starter was dragging extreamly trying to turn the engine and running the battery down. I hooked up jumper cables to it and using the car battery it started again. Once again it ran about 20 seconds before dying. Trying once again the top of the starter broke. (It was the original B & S starter that came with the motor in 1990) I put a cheaper knock off starter on it and it dragged as well not turning the motor fast enough to start it. I pulled the spark plug removing all compression and the starter turned it much better but after putting it back in the starter would not turn it enough to start it. I tried until the knock off starter actually started smoking a little bit.

Does a B&S starter have more torque than an off brand?

Can I get a higher torque starter?

What do you guys think?
Thanks,
Chuck
 

bertsmobile1

Lawn Royalty
Joined
Nov 29, 2014
Threads
64
Messages
24,647
pull the plug and see if the starter can spin the engine quickly.
If not then something inside is too tight.
Did you lube the rod & crank when you installed them ?

Did you turn the engine over by hand checking for tight spots.

And yes there is a high torque starter but it you are stripping the bendex gear the problem is not in the starter.
 

Chuck Gibson

Forum Newbie
Joined
Mar 21, 2016
Threads
1
Messages
6
I pulled the spark plug removing all compression and the starter turned it much better but after putting it back in the starter would not turn it enough to start it. I tried until the knock off starter actually started smoking a little bit. Does B&S starters have more torque?
 

Chuck Gibson

Forum Newbie
Joined
Mar 21, 2016
Threads
1
Messages
6
This is some feedback I got from another site. Have you ever heard of this?....

B-S has a compression release built on the cam shaft . So the starter has enough guts to spin over. The release would either break or the lift pin would wear off or the spring would break. Remove the head & turn the flywheel around by hand , watch the valves the ex. valve should lift off the seat a bit just before tdc of piston. It should stay loose just past tdc. to check -turn ex valve with your thumb at tdc ex stroke. This is a good way to be sure that cam to crank timing is correct. There was a lot of this trouble with the cam release on the 10 & 12 .5 hp engine which was the same engine. Changed many many of these cams. Check & double check this .
 

bertsmobile1

Lawn Royalty
Joined
Nov 29, 2014
Threads
64
Messages
24,647
Yes but as I am not there I have to make some assumptions.
As you are mechanically competant enough to rering your engine I was assumed that you had double checked your valve lash and compression release.

However the reason for running the engine sans plug was to determine if everything inside was in order.
If the decompression is not working the starter will spin for 3/4 of a turn then hang just before TDC which is not what you described.
Reading your post it sounds like the starter will not turn the engine period.

So the next thing on the check list is the valve clearence.
If it is too big the decompressor will not work.
I have run the inlet as tight as .002" on some engines to compensate for wear on the cam
 

Tinkerer200

Well-Known Member
Joined
Mar 14, 2015
Threads
4
Messages
913
Well I don't know how anyone can give you accurate info without knowing the engine model number since there are multiple 10 hp B&S vertical shaft engines.

Second, never try to make a starter turn an engine for more than 3 - 4 seconds at a time or you will over heat the windings causing them to loose efficiency, permanently. "Let the smoke out," well you fixed that one.

Walt Conner
 

Chuck Gibson

Forum Newbie
Joined
Mar 21, 2016
Threads
1
Messages
6
Yes but as I am not there I have to make some assumptions.
As you are mechanically competant enough to rering your engine I was assumed that you had double checked your valve lash and compression release.

However the reason for running the engine sans plug was to determine if everything inside was in order.
If the decompression is not working the starter will spin for 3/4 of a turn then hang just before TDC which is not what you described.
Reading your post it sounds like the starter will not turn the engine period.

So the next thing on the check list is the valve clearence.
If it is too big the decompressor will not work.
I have run the inlet as tight as .002" on some engines to compensate for wear on the cam

LOL. I am competant enough to learn,,,,sometimes the hard way mind you. I have rebuilt V-8's quite a few times just never a small engine such as this little B&S. I guess the smallest engine I have tore apart and rebuilt is the Fergusun Ford 9N. I checked the valve clearance when building it but out of my lack of knowledge I merely set the valve lash with the valves closed... Now I know that the piston needs to be 1/4" past TDC. In the first post I mentioned that I had pulled the plug and the engine would spin all the way around. I have new parts on the way and I am looking forward to trying this again!
Thanks for your help.
Chuck
 

Chuck Gibson

Forum Newbie
Joined
Mar 21, 2016
Threads
1
Messages
6
Well I don't know how anyone can give you accurate info without knowing the engine model number since there are multiple 10 hp B&S vertical shaft engines.

Second, never try to make a starter turn an engine for more than 3 - 4 seconds at a time or you will over heat the windings causing them to loose efficiency, permanently. "Let the smoke out," well you fixed that one.

Walt Conner

I'm so sorry. I can't believe I failed to put that on my first post. The model is: 255707 Type: 0126 01 Code: 90010431;
After using forums for years rebuilding V8's, tractor engines even appliances it seems like starting with the model # would be automatic. LOL
The conflicting information I have received now is rather it is the exhaust valve or the intake valve that actually relieves the compression I read in the B&S manual that some of the engines used the intake valve to relieve it. It does not specify which ones. It is not one of the models with the mechanical release on the exhaust valve.
Any ideas?
Thanks again for your help!
Chuck
 

Tinkerer200

Well-Known Member
Joined
Mar 14, 2015
Threads
4
Messages
913
"Any ideas?"

Yes, current B&S engines of 10 hp and up use the Intake Valve for compression release except Vanguard V twins which do use the exhaust. I can send you a Service (Overhaul) Manual for your engine IF you like. Address below, put in proper format and remind me engine model number and what you want.

Walt Conner
wconner5 at frontier dot com
 
Top